Korean Journal of Optics and Photonics (한국광학회지)

Optical Society of Korea (한국광학회)
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Anisotropic Whispering Gallery Modes Formed in Various Transformation Cavities

다양한 변환 공진기에 형성되는 비등방성 속삭임의 회랑 모드

  • Kim, Inbo (Digital Technology Research Institute, Kyungpook National University) ;
  • Choi, Muhan (Digital Technology Research Institute, Kyungpook National University)
  • 김인보 (경북대학교 디지털기술연구소) ;
  • 최무한 (경북대학교 디지털기술연구소)
  • Received : 2018.05.11
  • Accepted : 2018.05.22
  • Published : 2018.06.25
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Abstract

We explain the basic principle of transformation optics, and introduce several design techniques for transformation cavities that can maintain the characteristics of whispering gallery modes (WGMs) even if the cavity is strongly deformed from a circular shape. As a method of obtaining various transformation cavities under a specific conformal mapping, we suggest a method of parallel movement of the initial cavity domain, and a method of rotating the ellipse as a cavity domain. The internal wave pattern and the far-field output characteristics of several designed resonant modes are numerically calculated. From these results, it is confirmed that a variety of GRIN resonators are possible for a given conformal coordinate transformation.

이 논문에서는 변환 광학의 기본 원리를 설명하고 이를 적용하여 공진기 모양이 원형으로부터 크게 변형되어도 속삭임의 회랑 모드(WGM)의 특성을 유지할 수 있는 다양한 변환 공진기 설계 기법을 소개한다. 특정 등각 변환 하에서 다양한 변환 공진기를 얻는 방법으로서 초기 정의역을 평행 이동시키는 방법과, 타원을 정의역으로 잡고 회전시키는 방법을 제시하였고, 이를 통해 설계된 몇 가지의 공진기 모드에 대한 내부 파형 및 원거리장 출력 특성을 수치해석적으로 계산하였다. 이러한 결과로부터, 하나의 주어진 등각 좌표변환과 관련된 다양한 GRIN 공진기가 가능하다는 것을 확인하였다.

Keywords

References

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